The Phase I objective is to demonstrate the feasibility of a soft-x-ray microscope and recording medium that will offer order-of-magnitude improvements in size, weight, cost, simplicity, and ease of use over conventional x-ray microscopes. The specific aims of our Phase I research are: (1) to build and test a working breadboard of a high-resolution tabletop soft-x-ray microscope; and (2) to produce a conceptual design of a Phase II prototype that will show the merit of proceeding to commercial production. The improvements are expected based on innovations in soft-x-ray sources and thin-film photosensitive media. The soft-x-ray source, a compact electron diode with properly chosen anode material, should produce copious line emission in the water window. The x-ray recording medium combines high photosensitivity with the high resolution of grainless photoresists. The result should be a novel compact, low-cost tool for biomedical researchers. It should make practical for the first time the widespread commercial availability of the unique capabilities of x-ray microscopes: high-contrast, high-resolution imaging of wet biological specimens with minimal preparation and the ability to map precisely minute distributions of chemical elements within specimens. PROPOSED COMMERCIAL APPLICATION: A tabletop soft-x-ray microscope is expected to find wide use as a standard tool for biomedical researchers, biochemists, drug companies, and university research scientists. The convenience of portability, wall-plug operation, and quick exposures with low cost (projected at a few thousand dollars) and large savings in sample preparation should make this tool valuable for imaging of biological specimens and high-resolution mapping of chemical elements within specimens.